Ladder



y 1931- cms. KINGSBURY 1,315,316

LADDER Filed Nov. 27, 1928 I N V EN TOR. Girer/es Gifi ys $0,

A TTORNEYS.

Patented July 21, 19 3 1 UETE STATES PATENT OFFICE LADDER Application filed November 27, 1928.

This invention relates to ladders used in connection with painting walls or doing other work thereon. For purposes of this nature it is desirable that the ladder used be disposed in such a position that the steps or rungs thereof are all equally spaced from the wall to be worked upon, that is, that the rungs or steps are substantially at right angles to the wall. In painting walls a certain pressure is exerted thereon by the painter and following the well known law of physics that to every action there is an equal and opposite reaction, there is a reverse pressure transmitted through the body of the painter to the ladder or other support that he may be standing on. Needless to say, it is desirable to decrease the danger of a laddertipping over as a result of this reverse pressure.

In general it is the object of this invention to construct a ladder provided with a suitable prop for bracing it against lateral thrusts.

More specifically it is the object of this invention to provide a ladder comprising a pair of spaced side stiles and a plurality of steps secured between said stiles, with a single prop secured at its upper end to said ladder and forming with the lower ends of said stiles, a three point support for said ladder, said points determining an obtuse triangle.

The invention possesses other objects and features of advantage, some of which, with the foregoing will be set forth in the following description of the preferred form of the invention which is illustrated in the drawings accompanying and forming part of the application.

Referring to said drawings, Fig. 1 is a side elevation of a ladder en bodying the object of my invention.

Fig. 2 is a front view elevation thereof showing the disposition of its lateral prop or brace.

Fig. 3 is an enlarged view of the upper end of the ladder showing its details of construction.

Fig. 4 is a vertical section taken on the plane indicated by the lined- 1 of Fig. 3.

Fig. 5 is an end view of the upper portion of the ladder looking in the direction indi cated by the arrows 55 of Fig. 3.

- 12 and 13 on which is mounted a platform 14.

Serial No. 322,141.

Fig. 6 is a vertical section taken on the plane indicated by line 6-6 of Fig. 5.

My invention contemplates the use of a conventional ladder comprising the usual side stiles 1 and 2 between which are secured in spaced relation with each other a plurality of steps or rungs 3. As shown in Figures 1 and 2 the ladder has been constructed of two longitudinally adjustable sections and since this particular feature forms no part of the invention, it may be accomplished by any one of numerous well known devices.

Secured to the upper end of the side stiles 1 and 2 are a pair of U shaped straps 4 and 5 which together with the ends of the side stiles form a pair of spaced bearings within which is journaled a rod or tube 6. The tube 6 is preferably somewhat longer than the width of the ladder and is permitted by the above construction to be adjusted longitudinally along its own axis and laterally with respect to the ladder. Latching means is providedfor locking the tube in any predetermined position which may conveniently take the form of a pair of cotter pins 7 and 8 engaged in any two of a plurality of aper tures'9 formed in the tube 6. The protruding heads and ends of these pins engage in the outer faces of the side stiles thereby maintaining the tube 6 in its adjusted position.

Secured also in the upper ends of the side stiles 1 and 2, by the same bolts 11 which serve to secure the straps 4 and 5, are brackets A triangular plate 15 having lateral flanges 16 is pivoted to the tube 6 by strap hinge extensions 17 and 18. Pivoted intermediate its ends to the lower apex of the plate 15 by means of a bolt 19, is a longitudinally adjustable prop 21. Passing through an aperture in the upper end of this prop and then any one of the plurality of apertures 22 with which said aperture may be made to register is a bolt 23 provided with a wing nut 24.

The lower ends of the ladder and its prop are adapted to be maintained in spaced relation by means of an adjustable brace 25 one end of which may be secured to the prop by a universal joint 26 while its other end may be notched to accommodate one of the lower rungs of the ladder.

' In use a ladder constructed as above described may be placed adjacent a wall as shown in Fig. 2 and maintained in spaced relation thereto by properly adjusting the position of the tube 6. The prop 21 is secured with its lower end in its extreme position #way from the wall. The tube 6 takes care of any lateral component of force resulting from a workman leaning toward the wall, while the prop 21 takes care of any reverse thrust or force transmitted to the ladder through the body of the workman while hearing against the wall in the act of painting or doing other work upon the wall, and by adjusting the prop so that the center of gravity of the top of the ladder is predominantly toward the bearing of the lateral bar support against the wall surface, this form of ladder structure may be used at much greater height than an ordinary ladder not so supported. The construction disclosed therefore provides a ladder of great stability and further one which due to the lateral disposition of its prop may be used to support one end of a plank; or two spaced ladders of this type may be conveniently used to support a plank between them and thus build a temporary scaffolding. Due to the adjustability of both the tube 6 and the prop 21 the ladder may be used on either a left or right wall. It is to be noted that the greatest stability is obtained when the lower end of the prop together with the feet of the side stiles from an obtuse triangle.

1 claim:

1. A ladder comprising steps, means to support said steps, prop means to support said ladder vertically from a point in offset laterally spaced relationship on either side and a frame co operating with said prop whereby the thrust of the support is directed on both sides of the transverse center of an upper portion of the ladder.

2. A ladder comprising steps, side stiles to support said steps, means to support said ladder from a point in offset laterally spaced relationship to, and at one side of, the transverse center of the ladder base, and means extending laterally beyond the stile on the other side of the ladder adapted to support said ladder in spaced relationship to a hearing surface for said last mentioned extending means.

8. A ladder comprising side stiles, steps connecting said stiles, a prop hingedly connected to said ladder adapted to support in vertical incline said ladder from a point in offset laterally spaced relationship to, and at one side of, the transverse center of the ladder base, and an adj ustably lockable supporting means extending laterally beyond the stile on the other side of the ladder adaptieiasie ed to support said ladder in spaced relationship to a bearing surface for said last mentioned extending means.

4. A ladder comprising side stiles, steps connecting said stiles, a lockable and transversely adjustable lateral support member, a frame hingedly connected to said ladder transverse the top portion thereof, a prop medially pivoted on said frame, and means to lock said prop against transverse pivotal movement with respect to the stiles.

5. In a ladder comprising a pair of supporting side stiles and steps secured between said stiles, a single prop secured at its upper end to said ladder and forming with the lower ends of said stiles a three point support for said ladder, said points determining an obtuse triangle.

6. A ladder comprising side stiles, steps connecting said stiles, lockable and adjustable means to laterally support said ladder at either side in spaced relationship to a surface, a frame transverse the upper portion of the ladder, and a prop co-operating with said frame and adapted to support said ladder vertically from a point in offset laterally space relationship to either side of the transverse center of the ladder base.

7. In a ladder comprising a pair of spaced side stiles and steps secured between said stiles, a frame hingedly mounted transverse the upper portion of the ladder, a single prop medially pivoted at its upper portion to said frame and forming with the lower ends of said stiles a three point support for said ladder, said points determining an obtuse triangle; and means provided at the upper end of said ladder for maintaining it in spaced relation with respect to a wall, said latter means being adjustable to either side of the ladder and lockable in its position. of the transverse center of the ladder base,

CHARLES Gr. KINGSBURY. 

